Nearly 400 people packed the auditorium of the Buffalo Museum of Science Tuesday evening to hear about new sightings of the ivory-billed woodpecker, long believed to be extinct.

The last confirmed sighting of the Campephilus principalis was in 1944. But now sightings have been reported in the bottom-land hardwood forests of Arkansas.

"The ivory-billed woodpecker has been extinct for my entire life," said Ron Rohrbaugh of the Cornell Lab of Ornithology, who grew up hunting, fishing and birding in rural Pennsylvania. "It didn't exist."

Not to be confused with the pileated woodpecker, the ivory-billed variety is larger, growing to 18 inches long and having a wingspan of nearly 30 inches. The male has a red crest, a lightning-bolt stripe and a white trailing edge along the wings.

"The last sighting that's universally accepted was in April 1944 [in Louisiana] by bird artist Don Eckelberry," Rohrbaugh said. "Then on Feb. 11, 2004, a kayaker, Gene Sparling of Hot Springs, Ark., saw one in the bayou" in Monroe County, Ark.

Hearing about it, the Cornell Lab sent Tim Gallagher to Arkansas and by spring 2004 there had been four sightings.

Rohrbaugh showed a 4-second video made by David Luneau on April 25, 2004 in Bayou De View, near the White River National Wildlife Refuge in Arkansas. "There is some skepticism over it," he said, "and we welcome it."

John Fitzpatrick, director of the Cornell Lab of Ornithology, published an article in Science magazine in December.

Calling the discovery "an exciting opportunity," Interior Secretary Gale A. Norton appeared at a press conference in Washington, D.C., last April 28 with Cornell Lab officials and Sparling, the kayaker.

Rohrbaugh also played a recording of the "kent-like" call of an ivory-billed woodpecker taken in 1935 in northern Louisiana.

"I think it's unconscionable that this bird disappeared from the southeastern United States and we never looked for it in a systematic way until now," he said. "If we had, the job of restoration would have been easier."

More than 20 paid, full-time searchers and 112 volunteers are combing the marshes, he said, looking daily for signs of ivory-billed woodpeckers.

"This species of woodpecker is the symbol of hope and resurrection," said Carroll Simon, acting president and CEO of the museum. "It was the third rail of birding for decades -- anyone who claimed to have seen one was called crazy."